In known inspection equipment for objects including information storage media such as hard disks or optical disks, heads for recording information in those storage media and reproducing the stored information, or silicone wafers, the inspection conditions including items to be inspected, machine operations associated with those items and data representing the criteria upon which the inspection results are based are manually set in correspondence with the type of the object to be inspected.
Those operations with the conventional inspection devices are time consuming and may cause a mistake in preparing the test conditions. The method employing air suction to clamp a disk has been generally adopted to actual use.
However, such a clamping mechanism which utilizes air suction suffers from a disadvantage in that it cannot retain the disk if the air supply should fail when a disk is clamped. Further, it requires ancillary devices such as a vacuum pump and filter making the size of the entire equipment larger and thereby increasing its production cost.
As part of the clamping mechanism for a disk, some prior inspection devices utilize a chuck portion which clamps a work piece of the disk, a tool and other objects, rotating in synchronization with a rotation shaft like a spindle applied in various machine tools.
In such a chuck section, it is known to release and close the chuck mechanism by sliding a driving shaft inserted in a hole of the rotary shaft by means of a hydraulic or pneumatic cylinder.
However, the hydraulic cylinder requires ancillary devices such as a hydraulic pressure generating device and pipings. Therefore, if it is employed as a drive source, the production costs of the equipment are increased, as well as the size thereof.
Further, the hydraulic cylinder is usually mounted on the rotary shaft. This serves to increase the load applied to the rotary shaft system, necessitating the use of a motor having an increased capacity for the purpose of driving the rotary shaft. This in turn increases the production cost and the size of the equipment.
If the pneumatic cylinder is used as a drive source to drive the chuck section, a large-scale ancillary facility is required, increasing the production cost of the equipment. The pneumatic cylinder is also often mounted on the rotary shaft. This therefore increases the load applied to the rotary shaft system and necessitates the use of a drive motor having a large capacity.
The pneumatic cylinder also suffers from problems of air leakage from the cylinder and a contamination from the exhaust.
To simplify the whole structure, it has been proposed that the sole driving shaft inserted within the rotary shaft may be pressed for the purpose of driving the chuck section. In this method, however, since the driving shaft alone slides every time the chuck is released or closed, bearings which journal the rotary shaft are overloaded while the driving shaft is caused to slide, reducing the life thereof and degrading the accuracy thereof.